The present invention is an improvement on milk flow sensors used in milking systems, particularly of the type marketed by Dairy Equipment Company under the trademark BOU-MATIC Milking Systems.
Milk flow sensors of this type are used to control automatic milking equipment for milking cows by detecting when the cow has finished milking and then providing a signal that controls the equipment to remove the teat cups from the cow's udder. The milk flow sensor consists of a chamber having an inlet and an outlet located below the inlet. A float having a disk valve mounted thereon is disposed in the chamber for substantially vertical movement in the chamber to open and close communication between the inlet and the outlet. A diaphragm and a diaphragm valve are mounted on the sensor to cover the chamber and serve to control air lines which regulate the teat releasing mechanisms.
The float and disk valve are initially elevated by a manually actuated arm member to establish communication between the inlet and outlet of the chamber which allows for the flow of milk into the chamber. The arm member is connected to an externally located lever which operates to move the arm member in the chamber. After a sufficient amount of milk is contained in the chamber to support the float and the disk valve so as to maintain open communication between the inlet and outlet, the arm member is manually returned to its original position to enable the float to descend to its original position after the chamber has been emptied of milk. When the float and disk valve are in their lowermost positions, the communication between the inlet and outlet is closed causing the diaphragm valve to be actuated to provide for the release of the teat cups from the cow's udder.
One disadvantage with this milk flow sensor is that the operator must wait until enough milk has entered the chamber to support the float before the arm member can be returned to its original position. A substantial amount of time can be saved if the arm member is automatically returned to its original position at the appropriate time.
It is the object of the present invention, therefore, to provide an improved milk flow sensor whereby automatic return of the arm member is provided.